'Vampire grave': A skeleton with the head between the legs, discovered in Gliwice, Poland. Photograph: Andrzej Grygiel/EPA

The world's media have been getting their teeth into the story of a "vampire grave" uncovered last week by archaeologists at a roadside construction site in the town of Gliwice in southern Poland. When four skeletons were found with their skulls placed between their legs, speculation followed that these were suspected vampires that had been prevented from rising from the grave through the once-ritualistic local practice of decapitation.

"It's very difficult to tell when these burials were carried out," Dr Jacek Pierzak, the lead archaeologist, told the Dziennik Zachodni newspaper. Early indications, he said, suggested the grave could be dated to the 16th century. Other clues possibly suggesting a vampire burial included the skeleton's lack of any personal items, such as jewellery. Meanwhile, other local newspaper reports noted that an alternative theory suggested they were not vampires, but victims of an execution at a known nearby gallows.

Whatever the truth – the Guardian adopts a firmly sceptical position on the undead – the discovery of so-called vampire graves is not uncommon across eastern Europe. Last year, archaeologists in Bulgaria found two medieval skeletons with iron rods driven through their chest. According to Bozhidar Dimitrov, who runs the National History Museum in Sofia, about 100 such skeletons have been uncovered in Bulgaria, with the gruesome practice known across the Balkans, where fear of vampires has been at its strongest over the centuries.

The root of the vampire legend goes right back to ancient Egypt and Greece, says Dr Tim Beasley-Murray, a senior lecturer at UCL's School of Slavonic and East European studies who teaches on a course entitled Vampires, Society and Culture: Transylvania and Beyond. The myth, he says, then spread up through the Balkans into eastern Europe where it proved fertile during the pre-Christian era: "There is a strong Slavic belief in spirits. Romanian folklore has vampiric figures such as the moroi and strigoi. The word 'mora' means nightmare. But these are common to many cultures. We often see bird- or owl-like figures that swoop down and feed on you."

But beyond the specific dread of vampires, there has long been a fear of the dead rising up to terrorise the living. In 2008, archaeologists found a 4,000-year-old grave in Mikulovice in the Czech Republic in which the skeleton had been weighed down at the head and the chest by two large stones. "Remains treated in this way are now considered as vampiric," Radko Sedlacek, the director of the East Bohemia Museum, told reporters at the time. "The dead man's contemporaries were afraid that he might leave his grave and return to the world."